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Full Discussion: Eval
Top Forums Shell Programming and Scripting Eval Post 302798505 by Corona688 on Wednesday 24th of April 2013 03:12:10 PM
Old 04-24-2013
Quote:
Originally Posted by rbatte1
I feel such a fool. Fortunately, I only use it to get an indirect variable
In BASH, you can get an indirect variable via
Code:
NAME="VAR"
VAR="ASDF"
echo "${!VAR}"

This is a bash-only feature sadly, I used to think ksh93 had it too..

Quote:
...or scheduled tasks reading in assignments from a parameter file that I control, which is a pretty rare need in itself.
You can set arbitrary variable names with the read builtin, which will work in any shell. This trick works because read takes a variable name, not the variable itself.

Code:
VARNAME="ASDF"
read $VARNAME <<EOF
this contents get assigned to asdf
EOF

echo $ASDF

This User Gave Thanks to Corona688 For This Post:
rbatte1
 

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LEARN ABOUT SUSE

platform::shell

platform::shell(n)					       Tcl Bundled Packages						platform::shell(n)

__________________________________________________________________________________________________________________________________________________

NAME

       platform::shell - System identification support code and utilities

SYNOPSIS

       package require platform::shell ?1.1.4?

       platform::shell::generic shell
       platform::shell::identify shell
       platform::shell::platform shell
_________________________________________________________________

DESCRIPTION

       The platform::shell package provides several utility commands useful for the identification of the architecture of a specific Tcl shell.

       This  package  allows the identification of the architecture of a specific Tcl shell different from the shell running the package. The only
       requirement is that the other shell (identified by its path), is actually executable on the current machine.

       While for most platform this means that the architecture of the interrogated shell is identical to the architecture of  the  running  shell
       this  is  not generally true. A counter example are all platforms which have 32 and 64 bit variants and where a 64bit system is able to run
       32bit code. For these running and interrogated shell may have different 32/64 bit settings and thus different identifiers.

       For applications like a code repository it is important to identify the architecture of the shell which will  actually  run  the  installed
       packages, versus the architecture of the shell running the repository software.

COMMANDS

       platform::shell::identify shell
	      This command does the same identification as platform::identify, for the specified Tcl shell, in contrast to the running shell.

       platform::shell::generic shell
	      This command does the same identification as platform::generic, for the specified Tcl shell, in contrast to the running shell.

       platform::shell::platform shell
	      This command returns the contents of tcl_platform(platform) for the specified Tcl shell.

KEYWORDS

       operating system, cpu architecture, platform, architecture

platform::shell 						       1.1.4							platform::shell(n)
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